I am new to LTspice and following this tutorial : http://www.simonbramble.co.uk/lt_spice/ltspice_lt_spice_tutorial_3.htm

I am using the proposed Jig : LTC3878 buck converter that use 2 MOSFET,
RJK0305DPB and RJK0301DPB.

These device definitions looks good in the Standard.mos file

.model RJK0301DPB VDMOS(Rg=.8 Vto=2.15 Rd=.9m Rs=.2m Rb=.5m Kp=170. Lambda=.06 Cgdmax=1n Cgdmin=.4n Cgs=4n Cjo=.56n Is=56p ksubthres=.1 mfg=Renesas Vds=30 Ron=2.3m Qg=32n)

.model RJK0305DPB VDMOS(Rg=.6 Vto=1.95 Rd=2.7m Rs=.7m Rb=1.3m Kp=40.8 Lambda=.07 Cgdmax=.96n Cgdmin=.05n Cgs=.98n Cjo=.98n Is=48p ksubthres=.1 mfg=Renesas Vds=30 Ron=6.7m Qg=8n)

The jig used to work fine as well as many others that involved a MOSFET.

Today, within LTspice, I performed a Tools->Sync Release command to update LTspice definitions ( as suggested in tutorial 1 ) Not sure if this update action is related to the error message but it so happens that since this update none of my simulations that involve a MOSFET are running anymore. LTspice will choke with the same error message

Unknown VDMOS Level :3

I am then directed to click the OK button and that’s it, no simulation, just a schematic on my screen.

All my other jigs are working fine. As soon as a MOSFET is involved I get this error message and a dead end. Google as no solution in view. I tried looking through the LTspice help with no result.

The Question : How can I get LTspice to run my MOSFET jigs with no error ?

Unknown VDMOS Level :3

Any help much appreciated.

  • 1
    \$\begingroup\$ Write to Mike. His full name is in the "Help/About" selection and his email address was at scad3 at linear.com. You can, at least, try and contact him. In my experience, he has been extremely helpful and will always respond in kind. Just ask for some help here. I'd bet you get a very useful answer in short order. \$\endgroup\$ – jonk Dec 5 '19 at 5:28

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